- In Finder, press the key 'option' and click on 'Library' under 'Go'.
- In library folder, scroll down to 'keychain'.
- Click on the arrow to the left of keychain to reveal what's under it.
- Delete everything under keychain, but not the keychain folder itself. (In my case, I had to delete 3-4 files and a folder).
- Restart the mac.
- Voila, you are done. No more annoying pop-ups.
In addition, go to Utilities
Click into Keychain Access
Select Login in the left pane
Go to file, delete keychain and references.